diff mbox

PATCH] Fix PR 31531: A microoptimization of isnegative of signed integer

Message ID alpine.DEB.2.20.1604151839040.1853@laptop-mg.saclay.inria.fr
State New
Headers show

Commit Message

Marc Glisse April 15, 2016, 4:42 p.m. UTC 
comparison, could be boolean for instance. Asking for 
tree_nop_conversion_p between @0 and that type seems strange. Also, you 
are not allowed to use TYPE_PRECISION on a vector type.
diff mbox

Patch

--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1896,10 +1896,13 @@  DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
  (for cmp (simple_comparison)
       scmp (swapped_simple_comparison)
   (simplify
-  (cmp (bit_not@2 @0) CONSTANT_CLASS_P@1)
+  (cmp (convert?@3 (bit_not@2 @0)) CONSTANT_CLASS_P@1)
    (if (single_use (@2)
-       && (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST))
-   (scmp @0 (bit_not @1)))))
+       && (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST)
+       && (TYPE_PRECISION (TREE_TYPE (@3)) == TYPE_PRECISION (TREE_TYPE (@2)))
+       && tree_nop_conversion_p (type, TREE_TYPE (@0)))
+   (with { tree newtype = TREE_TYPE (@1); }
+    (scmp (view_convert:newtype @0) (bit_not @1))))))

Could you explain in English what you are doing?
'type' is always the outer type, in this case the result of the